1. The series of jaw crushers are mainly used for middle crushing and fine crushing of mid-hard ore and rocks in the sections of metallurgy, mining, chemical industry, cement, construction, ceramics together with refractories. 2.These crushers are most suitable to crush all kinds of soft and hard ore whose compressive strength is not higher than 300 Mpa. The maximum lumpiness of materials to be crushed should follow the technical data chart. Operating principle: The motor drives the belt wheel, and makes movable jaw up and down by eccentric shaft. When the movable jaw rises, the angle between the fixed jaw and movable jaw gets larger, and the materials can be crushed to reach the crushing target. When the movable jaw is down, the angle between the fixed jaw and movable jaw becomes smaller. The movable jaw plate leaves the fixed jaw plate under the function of drawbar and spring. And then the crushed materials are discharged from the lower outlet of the crushing cavity.